Critical current evaluation of BSCCO stacked tapes

Abstract Critical current of HTS stacked tapes is usually much smaller than the total summation of all critical currents of the tapes. This is mainly due to the self-magnetic field, and so far its behavior has been modeled by assuming constant current density distribution across the tape or by a numerical method with an assumption of J c which is dependent on the normal magnetic field to the tape surface but independent of parallel magnetic field. To predict the critical current of the BSCCO stacked tapes more exactly, it is necessary to calculate the critical current distribution across the stacked tapes. Since the critical current distribution across a tape is highly dependent on the strength and incident angles of magnetic field, which is the sum of external and self-magnetic fields, we need to rely on numerical analysis to get correct answers. We used a numerical model to calculate the critical current of stacked tapes. For this purpose we measured J c – B curves of a BSCCO tape for various incident angles between the magnetic field and tape surface. Using this experimental data, the critical current distribution across the stacked tapes was calculated for different stacking shapes. In this paper, the calculated critical currents are compared with the experimental data for one to five stacked tapes to prove the validness of the model, and we analyze the critical currents for various stacking configurations.